Interesting question.
I think Hayden Mullins (my #52, not ranked by SP) is a guy not on many people's radars who could really pop this year if he's finally healthy. He struck out a fairly preposterous 15 hitters in 6.1 IP last season after being drafted in the 12th round in '22. His stock fell because he came with an arm injury, but he's a high stuff guy.
David Sandlin (my #12, SP #13) isn't a sleeper, but his stuff has gone up a couple levels in the pitching lab this off season & I think it's interesting he's on the same pitching staff as a couple guys in Cooper Adams (#191) & Conor Sensabaugh (#200) who have like no pedigree of college success, but did well in I believe the Tread lab to earn spots on this team. So they aren't sleepers per se... but it will be fascinating to watch how the lab grown pitchers do this year.
I also think guys like Early (#57) & Feeney (#129) are interesting because they got the Greenville placement over guys like Duffy & Wehunt from the same class, & over guys like Paez & ERC.
JWY (#99) has flashed nice stuff this spring & is quite a character. If he's healthy & pitches well, he could easily be in Portland before long.
On the infield, I don't see a lot of sleeper potential. Luis Ravelo (my #51, SP #44) plays defense that will be fun & Ahbram Liendo (#127 but probably should be higher) is a menace on the bases so he could be a fun watch (30 steals in only 71 games last year before getting hurt). Both of those guys need to cut down on their strikeouts to be truly interesting, but both are 20.
Hoping for breakout seasons from Cutter (#37) & especially Mikey (#17), but neither are sleepers.
Greenville seems to have way too many "Outfiedlers" as the graphic calls them. Juan Chacon (#79) seems like the biggest sleeper candidate from the group as he looked good this Spring. He's another guy like Liendo who stole a lot of bases in Salem (20 in 57 games) while being an ~average hitter, but then earned a promotion. Chacon is 21 & showed a bit of pop & defensive skill in Spring Training.
Castro & Campbell aren't sleepers, but I'm glad Campbell is finally getting some love from SP & Speier et al after being way underrated. Lopez & Gonzalez are both returning players who may get some 1B & DH reps.
The fact that Caden Rose (#111) received a Greenville placement is a really good sign after he didn't get into any game action after being drafted in the 7th round last year & receiving an underslot bonus. There isn't anything that impresses me that much in his profile, but you never know.
I wouldn't really call any of the catchers sleepers. I'm a Ronald Rosario (#84) stan, but not really sure he's got a next gear unless he can drastically cut his 30% k-rate. He only recently turned 21, though.
This was a really long non-answer for which I apologize, but the definition of "sleeper is always challenging".
If I'm going to pick one pitcher & one hitter who aren't currently in the SP top 60 to crash the party, I'll go Hayden Mullins & Juan Chacon.
